Aquamacs is a Mac-like version of the powerful
Emacs text editor that runs as a standard OS X
application. It features extensive customization
that enables it to conform better with Apple's
standard Human Interface Guidelines (HIG) than
standard versions of the editor do. It provides a
more Mac-like user experience than Carbon Emacs.

The Autotoolset package complements the GNU build
system by providing automatic generation of legal
notices, automatic generation of GNITS-standard
directory trees, a rudimentary portability
framework for C++ programs, support for writing
portable software that uses both Fortran and C++,
additional support for writing software
documentation in Texinfo and LaTeX, and a manual
introducing both Autotools and the GNU build
system in a unified task-oriented manner.

BHL is an Emacs mode which enables you to convert
plain text files into HTML, LaTeX, Texinfo, SGML
(Linuxdoc), and TXT files. The BHL mode handles
three levels of sections, many sectioning styles,
common font-styles, any kind of lists, tables,
URLs, horizontal rules, and Wiki names. BHL
handles a list of links (lol) and a table of
contents (toc): you can browse the lol and the
toc, insert them where you want, and update the
sections' numbers with one keystroke.

Bintris is a Tetris-style game for Emacs. Instead
of the usual Tetris shapes, the blocks are ones
and zeros, and the player needs to match a target
decimal number with binary numbers in order to
collapse rows.

BlogMax makes it easy to use Emacs to maintain a Web log. You define templates
and an FTP site for uploads. Most of your site's content is defined by text
files. Saving a text file automatically wraps the template around it, expands
macros and shortcuts, and saves the HTML file. Other commands in "weblog" mode
upload files via FTP, create an RSS file, yank links or blockquotes into the
buffer, create shortcuts, etc. The BlogMax Web site was, of course, created
with BlogMax. It has been tested in Emacs 20.3.1 on Windows and Emacs 20.4.1 on
Mandrake Linux.

CMUCL is a free, high performance implementation of the Common Lisp programming language which runs on most major Unix platforms. It mainly conforms to the ANSI Common Lisp standard. CMUCL provides a sophisticated native code compiler; a powerful foreign function interface; an implementation of CLOS; the Common Lisp Object System; which includes multimethods and a metaobject protocol; a source-level debugger and code profiler; and an Emacs-like editor implemented in Common Lisp. CMUCL is maintained by a team of volunteers collaborating over the Internet, and is mostly in the public domain.

CSDE (CSharp Development Environment for X/Emacs)
is a full-featured mode for CSharp development in
Emacs/XEmacs. Features include font-lock,
indentation rules, grammatical parsing, auto
complete, automatic documentation of classes,
documentation checking of classes, namespace
generation, using sorting, and much more. This is
a conversion of the JDE for Emacs / XEmacs to CSharp.